Method of forming sheet-metal cylinders.



R. E. DUNHAM. METHOD OF FORMING SHEET METAL CYLINDERS.

Patented Dec. 4, 1917.

APPLICATION FILED FEB. 19, 1914.

(QM/Wow? RAY E. DUNHAM, or BEREA, OHIO, Assienon TO THE DUNHAM UNITED STATES PATENT omen COMPANY, "or IBEREA,

OHIO, A CORPORATION OF OHIO.

METHOD or FORMING SHEET-METAL CYLINDERS.

Specification of Letters Patent.

' Patented Dec. 4,1917.

Application filed February 19, 1914. Serial No. 819,695.

To all whom it may concern:

Belt known that I, RAY E. DUNHAM, a

citizen of the United States, resident of Berea, county of Cuyahoga, and State of Ohio, have invented a new and useful Ina-- provement in Methods of Forming Sheet- Metal Cylinders, of which the following is a specification, the principle of the invention being herein explained and the best mode in which-I have contemplated apply-- ing that principle, so as to distinguish it from other inventions.

My invention relates to methods of forming sheet-metal cylinders, its object being to effectsuch formation in an efficient and economical manner. My said invention relates more specifically to and is peculiarly adapted for usein connection with the formation of sheet metal cylinders whose outer surfaces are required to be true or practically true cylindrical surfaces, such as for instance, is the case in the drums or cylinders of lawn or land. rollers, and particularly where such rollers are to be used for rolling tennis courts. In order to be acceptable for rolling tennis courts, the outer surfaces of the rollers should be smooth, without ridges or other superficial inequalities and truly cylindrical in form, as will be readily understood by those skilled in the art.

Heretofore it has been the practice in forming the outer or cylindrical shell of the drum of such roller, to take a sheet of steel of suitable dimensions, pass it between suitable rollers to bend it into cylindrical form, then bring the longitudinal edge-portions into abutting contact, and then fuse or weld these abutting ends to each other by the application to the outside or convex surfaces near the abutting surfaces, of a welding or fusing temperature, usually by means of an oxyacetylene flame. This fusing or welding together of theseends is ordinarily assisted by the simultaneous application of welding iron, to the joint, such application being similar to the use of solder in the ordinary soldering process.

Such practice results in the formation upon the outer surface of the cylinder, of a longitudinal rough ridge of metal, which in order to make the roller in which the drum isto be used, conform to the commercia1requirements,must be removed. Such removal involves an expensive operation, the elimination of which is economically desirable and advantageous.

-A specific object of my invention is there fore to effect the union of such abutting surfaces without the formation of such ridge and to in that way perform a minimum number of operations in the course of manufacture.

My said invention consists of a method i set forth in the claims.

In the annexed drawing: Flgure 1 represents an end new of a sheet hereina'fterfully described and particularly of steel used in constructing alawn-roller drum. v a I Fig. 2 represents a slmllar view showing the form of the sheet after the firststep in the formation of the drum is completed.

Fig. 3 represents an end view of the sheet.

section showing the-partial union of said end-portions.

Fig. 7 is a similar 'se'ction showing-the completed joint.

. In carrying out the process my invention, the sheet 1, isthrough suitable rolls (not shown) and in a manner well known to those skilled in the art, to form a cylindrical shell with the free embodying first passed ends abutting as shown in Fig. 3. In order a to make the shell truly cylindrical, one end is, however, first bent into curved form before passing through such rolls, as shown in Fig. 2, that end first passing through the rolls being so bent. This preliminary bending is efiected by anysuitablemeans (not shown) preferably by means of properly adjusted rolls or. dies. v

The sheet having been manipulated as above described, an oxy-acetylene flame is then dire ted uponthe exposed inner or concave surfaces which are adjacent to the inner end of the abuttingsurfaces 2 and 3, as shown in Fig. 6, and the welding or fusing temperature so producedapplied until the corresponding metal fuses and the zone of fusion extends outwardly. to almost but not qulte the other and outer end of such abutting surfaces.

. ing

Welding iron may be used in said described operation in the usual manner. An almost complete'joint will thus be formed with an inner longitudinal ridge or mass 4 acting as a reinforcement, the outer surface of the shell being, however; undisturbed.

The flame is then directed to the outside or convex surface along the outer ends of the abutting surfaces, @and the metal fused until the joint is complete. The ununited metal uponthe outside being of small mass, the final fusing operation is performed with little disturbance to the metal and the use of only with the result that the continuity of the cylindrical outer contour is only slightly disturbed and is hence a negligible quantity, as

shown in Fig. 7

A shell is thus formed having the previously described characteristics of outer contour. 1

Having fully described my invention, what I claim and desire tosecure by Letters Pat ent iszr 1. In a method of forming sheet-metal cylinders, the steps which consist in bringtwo sheet-ends into abutting contact; subjecting the exposed surfaces of 'metal' which are adj acent to one end of the abutting surfaces to a welding temperature until the weld extends to a point near-the opposite a small amount of welding iron,

' almost through the seam,

end of said abutting surfaces and well through the seam; and then subjecting the metal adjacent to said opposite end to a cylinders which consists in bending a sheet into cylindrical form; bringing the two lon- 40 gitudinal ends into abutting contact; then subjecting the metal upon the concave side of the sheet and which is adjacent to the contacting surfaces, to a fusing temperature until a weld nearly through the joint is formed; and finally subjecting the metal upon the convex side to a fusing temperature until the joint is, completed.

3. The method of forming smooth surfaced hollow cylinders, which consists in 50. bending a smooth surfaced sheet into cylindrical form with the ends abutting, welding together said sheet from the interior, with a welding flame, until the weld reaches ing the weld from the exterior by means of a similar flame, whereby a smooth surfaced cylinder having little or no seam is produced.

Signed by me, this 17th day of February,

*- RAY E. DUNHAM. Attested by- A. F. EHRBAR, H. D. MATTISON.

and then complet- 

